1. Field of the Invention
The present invention relates to a suspension arm adapted for use in a suspension system of an automotive vehicle, and more particularly to a suspension arm of the type which has a pair of spaced mounting portions mounted on a vehicle body structure at two positions spaced in a fore-and-aft direction of the vehicle and a support portion supporting thereon a road wheel.
2. Description of the Prior Art
Disclosed in Japanese Patent Laid-open Publication No. 135805/1992 is a lower suspension arm of the type which is composed of a pair of long and short arm members mounted at their one ends on a vehicle body structure at front and rear positions spaced in a fore-and-aft direction of the vehicle. The long arm member is adapted to support a road wheel at its other end, while the short arm member is connected at its other end to an intermediate portion of the long arm member by means of a pair of spaced bolts to provide a low stiffness portion. In the lower suspension arm, the connected portion of the arm members is buckled deformed when applied with a great impact force in a fore-and-aft direction of the vehicle.
In such a lower suspension arm as described above, however, the stiffness of the arm members in a lateral direction of the vehicle is decreased as well as the stiffness in the fore-and-aft direction of the vehicle. As a result, the suspension arm can be deformed when applied with an impact force in the lateral direction of the vehicle in a sudden braking operation.